I stumbled upon this list of "hidden features of perl" and thought it'd a good idea if I got some of your replies as well!

http://stackoverflow.com/questions/161872/hidden-features-of-perl

Just as on the site, here a few "requirements":

Try to limit answers the Perl core and not CPAN

Please give an example and a short description

In reply to Hidden features of Perl by vxp

Title:
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